采用石蜡基粘结剂体系制备注射成形Sm_2Co_(17)永磁体  

Sm_2Co_(17) permanent magnets prepared by PIM with PW-based binder

作　　者：田建军[1] 左志军[1] 潘德安[1] 张深根[1] 曲选辉[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《北京科技大学学报》2008年第12期1374-1377,共4页Journal of University of Science and Technology Beijing

基　　金：北京市自然科学基金资助项目(No.2073026)

摘　　要：选择石蜡基热塑性粘结剂,采用粉末注射成形(PIM)工艺制备烧结Sm2Co17永磁体.粘结剂由PW、HEPE、LEPE、PP和SA组成,通过分析喂料流变性能和磁体残碳含量,确定合适的组元配比(质量比)为PW∶LEPE∶PP∶SA=7∶1∶1∶1.在氩气和氢气混合气氛下热脱脂,永磁体的碳、氧含量较低.最终得到永磁体的磁性能为:剩磁Br=0.51T,内禀矫顽力Hcj=168kA.m-1,最大磁能积BHmax=21.3kJ.m-3.与传统方法制备的永磁体相比,PIM永磁体退磁曲线的方形度较差,磁性较低.造成磁体性能较差的原因是残碳的质量分数较高(≥0.33%),较高的碳含量导致磁体中出现高熔点的非磁性相ZrC,使Zr的有效含量降低,片状相和1∶5相体积分数减少,胞状显微组织和微观结构被破坏,磁性能下降.因此,采用PIM工艺制备高性能烧结钐钴永磁体,其关键是降低磁体中的残余碳含量.Powder injection molding （PIM） was used to prepare sintered Sm2Co17 magnets with paraffin wax （PW） based binder, which consists of 70% PW, 10% LEPE, 10% PP, and 10% SA （mass fraction）. The binder is removed by thermal debinding in the mixing atmosphere of argon and hydrogen. The magnetic properties of the sintered PIM magnets are remanence Br = 0.51 T, intrinsic coercivity Hcj = 168 kA· m^- 1, and maximum energy product BHmax = 21.3 kJ· m^- 3. Compared with commercial magnets, the magnetic properties are poor because the PIM magnets have high carbon mass fraction （0.33 % ）. Carbon consumes the effective content of Zr and forms high melting-point nonmagnetic phase （ZrC）, which results in the decrease in volume content of lamella phase and 1 ： 5 phase. Deterioration of the cellular structure and SEM structure leads to the decrease in magnetic properties of the PIM magnets. It is concluded that residual carbon in the magnets should be removed when the sintered magnets is prepared by PIM.

关 键 词：SM2CO17永磁体 粉末注射成形 粘结剂 石蜡 碳含量 

分 类 号：TM273[一般工业技术—材料科学与工程]